Pipe-wrench.



J. A. WATSON.

PIPE WRENCH.

APPLICATION FILED JUNE 5, 1912.

Patented Oct. 13, 1914.

THE NORRIS PlTlR! CO.. FNOID-LITND. vnsmnmur: L' I JOHN A. WATSON, 0F RAYMOND, ILLINOIS.

PIPE-WRENCH.

Specification of Letters Batent.

Patented Oct. 13, 1914.

Application filed June 5, 1912. Serial No. 201,755,

To all whom it may cone-em:

Be it known that I, JOHN A. VVATsoN, a citizen of the United States, residing at Raymond, in the county of Montgomery and State of Illinois, have invented certain new and useful Improvements in Pipe Wrenchcs; and I do declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to the letters and figures of reference marked thereon, which form a part of this specification.

This invention relates to pipe wrenches and has for its object to provide a pipe wrench which is readily adjustable to pipes of different sizes. and diameters and which is so constructed and arranged that the biting action of the jaws of the wrench increases in proportion to the strain placed upon the wrench.

A further object of the invention is to provide a pipe wrench having an eccentricalgly pivoted jaw which is so arranged in relation to the fixed jiaw that when the wrench is in operation strain placed on the wrench tends.- to close the. pivoted jaw in such manner as to increase the biting action of the jaws on the pipe.

With these objects in view the invention consists in the novel construction of the pivoted aw and in the relative arrangement andlocation of said jaw in relation to the fixed jaw.

Referring to the accompanying drawing: Figure 1 is an elevation of a pipe wrench constructed in accordance with this invention illustrating the same applied to a small pipe. Fig. 2 is a similar view illustrating the wrench applied to a pipe of larger diameter, and Fig. 3 is an edge view of the wrench Like numerals of reference indicate the same parts throughout the several figures in which;

1 indicates the wrench which comprises the handle 2, fixed jaw 3 and pivoted jaw 4. The fixed aw 3 is curved in the manner as shown in the drawing, the inner surface of the jaw 3 being curved upon the arc of a true circle as shown and provided with a plurality of teeth 5 having the perpendicular walls 6 of their teeth 5 at suitable intervals apart and in the radii of said circle, as shown in Figs. 1 and 2. As will appear from Figs. 1 and 2 that portion of the wrench adjacent the fixed jaw is restricted at 8 in such manner as to provide a curved shoulder 9 on each side of the wrench, while the pivoted jaw 4 is bifurcated in order to Y straddle the resulting fin like tongue formation 8 of the Wrench in the manner illustrated in Fig. 1, the bifurcated portion of the pivoted jaw 4 terminating at the dotted line drawn through the pivoted jaw 4 in the manner shown in Fig; 1. The pivoted jaw 4 is circular in plane and is provided on the periphery nearest the fixed jaw 3 with a plurality of teeth 10 having their perpendicular walls in the radii of said pivoted jaw, as shown in Figs. 1 and 2. It will be seen from referring to Figs. 1 and 2 that the pivoted jaw 4 is pivoted a considerabic distance from the teeth 5 of the fixed jaw 3, each succeeding tooth of said jaw 3, being at a greater distance from the pivotal point 7, while it will be seen that each succeeding tooth on the pivoted jaw 4 is at a greater distance from the pivotal point 7, the toothed surface of the two jaws thus diverging from each other toward their receiving edges, this arrangement being a material feature of this invention It will be noted that the engaging teeth of the two jaws will lie in alinement when the center of the pivoted jaw coincides with the center of the toothed arc of the fixed jaw, the perpendicular walls of the teeth of the pivoted jaw being on radial lines of the pivoted jaw while also the perpendicular walls of the teeth of the fixed jaw are in line with the radii of the, pivoted jaw when the center of said pivoted jaw coincides with that of the toothed arc of the fixed aw.

The toothed surfaces when in a closed position form a complete semicircle, the diameter of which passes through the center of the movable jaw when the same is in a closed position, while the pivot 7 is located on the line of-the diameter so that when the movable jaw 4 is in a closed position the diameter of the semicircle formed by the two toothed surfaces passes through the center of the movable jaw, and through the pivot 7. A right angle triangle formed on this diameter line the base of which is the distance between the center of the movable jaw and the pivot 7 and the hypotenuse thereof is the distance between the pivot 7 and the periphery of the toothed surface of said movable jaw, will always have its vertical side parallel with a radius of the fixed jaw in any position of the movable jaw when the distance from the periphery of the movable jaw to the pivot 7 is equal to one fourth the hypotenuse of the said right angle triangle. The result of this is that a line passing through the center of the movable jaw will always be radial to the tangents of the movable jaw and fixed jaw. The perpendicular walls of the teeth being formed on radii of the two jaws, the said walls of said teeth on the two jaws at the said tangents and adj aoent thereto mustnecessarily be parallel. A round element engaged by the two jaws in any position of the movable jaw will therefore have its center on a line passing through the center of the two jaws so that the tangents of the element engaged and those of the two jaws will always be parallel. As the perpendicular walls of the engaging teeth of the two jaws are always parallel and the tangents of the two jaws and the engaged element are likewise parallel the most efficient gripping action is imparted to the wrench.

Having thus described the several parts of the invention its operation is as follows: The pivoted jaw 4 being arranged in relation to the fixed jaw 3 as shown in the drawings said jaw 4 can be swung on the pivot 7 to accommodate any size of pipe to which the wrench is applicable, it being of course understood that this wrench must be made in different sizes in order to accommodate the largest pipes much in the same manner as is the custom in the production of pipe wrenches of the usual type. When, however, a small pipe is to be engaged and the pivoted jaw 4 is in position shown in Fig. 1 strain arranged on the handle in the direction of the arrow shown in'Fig. 1 causes the biting teeth 5 to engage the pipe and at the same time causes the biting teeth 10 on the pivoted jaw 4 to engage the pipe, the direction of stress on the pivoted jaw 4 being indicated by the dotted arrow shown in Fig. 1, and by reference to Fig. 1 it will be seen that this strain on the pivoted jaw 4 is in such a direction as to tend to cause said jaw to approach the fixed jaw 3 thereby causing said pivoted jaw 4 to bite the pipe harder as the force is increased on the handle in the direction of the arrow indicated in Fig. 1.

In the illustration shown in Fig. 2 where a larger pipe is shown it will be seen that the force on the pivoted jaw 4 is in the direction of the dotted arrow in Fig. 2 which direction tends to cause the pivoted jaw 4 to approach the fixed jaw 3 in such manner that the greater the force applied to the handle in the direction of the arrow in Fig. 2 the harder the pivoted jaw 4 will bite into the pipe. Consequently with this construction and the arrangement of the teeth on the pivoted jaw the tendency of the jaw in operation will at all times be in the direction of approach to the fixed jaw 3, thus insuring an absolute engagement between the two jaws and the pipe.

Having thus fully described the invention what I claim as new and desire to secure by Letters Patent of the United States is A wrench of the type described including a handled fixed jaw having an arcuate toothed face, the handle of said jaw having a fin-like formation underlying the arcuate toothed face of said jaw and a partially toothed pivoted circular jaw eccentrically hung from said fin-like formation, the said two toothed surfaces of the said jaws forming a semicircle when the pivoted jaw is in a closed position, the pivot of said circular jaw being located on the diameter line of the said semicircle formed bv said toothed surfaces, each tooth on said jaws having a perpendicular wall in line with the radii of said pivoted circular jaw when the said circular jaw is in a closed position, the perpendicular walls of the teeth of said fixed jaw being parallel with the radial walls of the teeth of the pivoted jaw when said pivoted jaw is in an open position, the pivotal point of the said pivoted jaw bearing a fixed relation to the diameter of the said semicircle formed by the said two toothed surfaces on said jaws substantially as described and for the purposes set forth.

In testimony whereof, I affix my signature, in presence of two witnesses.

JOHN A. WATSON.

Witnesses:

J. E. McDAvID, J. C. TERRY.

coplel of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. C." 

